title: The value of abnormal muscle response monitoring during microvascular decompression surgery for hemifacial spasm.
abstract: OBJECTIVE
  Abnormal muscle response (AMR) to the electrical stimulation of a branch of facial nerve is a specific electrophysiological feature of primary hemifacial spasm (HFS). The aim of this study was to evaluate the value of AMR monitoring during microvascular decompression surgery (MVD), and the correlation between the AMR changes and the clinical outcomes.
  
  
  METHODS
  This study included 241 cases of MVDs. Intraoperative AMR monitoring was performed for each subject. The patients were divided into two groups based on whether the AMR-disappeared or not following decompression of the facial nerve.
  
  
  RESULTS
  Postoperatively, 229 (95.0%) patients were relieved from the spasm, 215 (93.9%) occurred in the AMR-disappeared group, 14 (6.1%) in the non-AMR-disappeared group. The correlation between intraoperative AMR abolition and HFS relief was statistically significant.
  
  
  CONCLUSIONS
  Intraoperative AMR monitoring was an effective assistant for a successful MVD for the patient with HFS. It is worth being routinely employed during the operation.
authors.affiliation: Department of Neurosurgery, XinHua Hospital, Shanghai JiaoTong University School of Medicine, The Cranial Nerve Disease Center of Shanghai, 1665 KongJiang Rd, Shanghai 200092, China. cadynj@hotmail.com
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Ying
authors.forename: Shi-Ting
authors.initials: ST
authors.lastname: Li
authors.forename: Jun
authors.initials: J
authors.lastname: Zhong
authors.forename: Xin-Yuan
authors.initials: XY
authors.lastname: Li
authors.forename: Xu-Hui
authors.initials: XH
authors.lastname: Wang
authors.forename: Jin
authors.initials: J
authors.lastname: Zhu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019299:Decompression, Surgical / Q000379:methods*; D004558:Electric Stimulation; D004576:Electromyography; D005152:Facial Muscles / Q000503:physiopathology*; D005154:Facial Nerve; D005260:Female; D019569:Hemifacial Spasm / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008297:Male; D008866:Microsurgery / Q000379:methods*; D055806:Microvessels / Q000601:surgery*; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome